The endowment of religious, charitable, and educational enterprises by the establishment of trusts in land, the income from which could be devoted to such uses, was an immensely popular form of pious expression in both medieval Christendom and the Islamic world. The motives for, and applications of such endowments differed markedly, however, between the two religious cultures. The endowment of prayers and masses for beneficiaries, living and dead, exemplified the sacramental and sacerdotal quality of pre-Reformation Christianity. This ritualistic and ecclesiastical use of endowments in Latin Christian Europe and the Orthodox East, a use dependent on the existence of a sacramental system and an institutional church, contrasted sharply with the broader application of the Muslim waqf, by means of which pious individuals and groups sponsored a wide variety of charities, explicitly life-oriented and quite unconnected with a corporate clerical establishment. The infinite multiplication of private acts of charity by devout Muslims manifested the moralistic bent of Islam, which aspired to recast society according to the norms of the Qur'an and sacred law. The contrasting uses to which the two religious systems put the gifts and legacies of the faithful reflected the operation of fundamentally different religious premises, whereas the institutionalization of these premises in a shared legal fiction, the trust, assured their enforcement in society and life.